Autotrophic nutrition ( absorption of water and salts )

Question 1

types of nutrition?

Answer 1

1) autotrophic nutrition
2) heterotrophic nutrition

Question 2

autotrophic nutrition:

Answer 2

simple complex
low energy —–>. high energy
inorganic organic

Question 3

heterotrophic nutrition

Answer 3

complex simple
high energy ——> low energy
organic inorganic

Question 4

heterotrophs are classified into?

Answer 4

.Holozoic
.parasites
.saprophytes

Question 5

Holozoic include?

Answer 5

.herbivores: feed on plants
.carnivores: feed on animal’s flesh
.omnivores: feed on both animals and plants

Question 6

parasites such as?

Answer 6

.Bilharzia worms
.orobanche plant

Question 7

saprophytes include?

Answer 7

.some fungi
.saprophytic bacteria

Question 8

saprophytism:

Answer 8

ability of some living organisms to decompose the organic remains or the dead bodies of the living organisms

Question 9

parasitism:

Answer 9

relation between two organisms, (parasite) depends on the other (host) by getting its food completely or partially from the host, causing different harms to the host

Question 10

autotrophic nutrition in green plants is occurred through two important processes, which are:

Answer 10

.absorption of water and salts process
.photosynthesis process

Question 11

root hair’s structure:

Answer 11

it is considered an extension of a single cell of (epidermis)

Question 12

root hair’s length:

Answer 12

4mm long

Question 13

root hair’s age:

Answer 13

few days or weeks, because the epidermis cells are teared from time to time, but they are regenerated continuously from the elongation zone of root

Question 14

suitability if root hair to its function:

Answer 14

1) being large in number and protruding outside
2) having thin wall
3) secreting a viscous substance
4) the solution inside its sap vacuole is more concentrated than the soil solution

Question 15

why are the root hair large in number and protruding outside?

Answer 15

to increase the surface area of water and salts absorption

Question 16

why does root hair have thin wall?

Answer 16

to permit the passage of water and salts through it

Question 17

why does root hair secrete a viscous substance?

Answer 17

to help these hairs to find their way easily among the soil particles and stick to them. so, they can fix the plant into the soil

Question 18

why does root hair have the solution inside its sap vacuole more concentrated than the soil solution?

Answer 18

to help the water passage from the soil to the root ( by osmosis )

Question 19

mechanism of water absorption

Answer 19

.diffusion phenomenon
.permeability phenomenon
.osmosis phenomenon
.imbibition phenomenon

Question 20

diffusion phenomenon

Answer 20

it is the movement of molecules from high concentration to low concentration

Question 21

permeability phenomenon
(permeable)

Answer 21

allow water and mineral salts to pass
EX: cellulose walls

Question 22

permeability phenomenon
(impermeable)

Answer 22

don’t allow water and mineral salts to pass
EX: walls covered by lignin or cutin or suberin

Question 23

permeability phenomenon
(semi-permeable)
(selective permeability)

Answer 23

-allow water to pass
-control the permeability of many salts
-prevent the permeability of sugar and amino acids, as they are large-sized molecules
EX: plasma membrane

Question 24

osmosis phenomenon

Answer 24

it is the passage of water through the semi-permeable membranes from a medium with high concentration of water molecules ( low concentration of salts) to another one with low concentration of water molecules (high concentration of salts)

Question 25

osmotic pressure

Answer 25

it is the pressure that causes the passage of water through semi-permeable membranes, due to the difference in concentration of dissolved substance (solutes) in water on two sides of the membrane

Question 26

Imbibition

Answer 26

the plant cell walls absorb water through solid particles, especially the colloidal ones that have the ability to absorb water therefore they swell and increase in volume

Question 27

examples of hydrophilic colloidal substance?

Answer 27

cellulose
pectin
protoplasmic proteins

Question 28

macro nutrients

Answer 28

in considerable quantities
-Nitrogen (N)
-Potassium (K)
-Magnesium (Mg)
-Iron (Fe)
-Phosphorus (P)
-Calcium (Ca)
-Sulphur (S)

Question 29

Macro nutrients importance?

Answer 29

-The nitrate, phosphate and sulphate salts work on converting the carbohydrates into proteins.
-Phosphorus enters in the formation of the energy carriers compounds (ATP).
-Iron is important for the building up of some co-enzymes which are required for the accomplishment of photosynthesis process

Question 30

micro nutrients

Answer 30

in very small quantities
Manganese ( Mn)
Zinc (Zn)
Boron (B)
Aluminium (Al)
Chlorine (Cl)
Copper (Cu)
Molybdenum (Mo)
Iodine ( I )

Question 31

Micro nutrients importance?

Answer 31

some of these elements work as activators for enzymes

Question 32

mechanism of mineral salts absorption

Answer 32

-diffusion phenomenon
-selective permeability phenomenon
-active transport phenomenon

Question 33

diffusion phenomenon ( salts absorption )

Answer 33

solutes move by diffusion from the soil solution (high-concentrated medium) and passthrough the cellulose walls (low-concentrated medium), due to the continuous movement of free ions.
under certain conditions, cations exchange may take place through the cell membrane

Question 34

selective permeability phenomenon (salts absorption)

Answer 34

ions reach the semi-permeable membrane, some of them are selected and allowed inside the cell to pass through it, while other ions aren’t allowed, according to the plant need, regardless of their size, concentration or charge.

Question 35

active transport phenomenon (salts absorption)

Answer 35

(ions diffuse from low concentration to high concentration) and the passage of any substance through the cell membrane, when it needs chemical energy

Question 36

active transport phenomenon (salts absorption)

Answer 36

ions diffuse from the soil solution (low concentration) to inside the cell (high concentration), the presence of chemical energy is needed to force these ions to move against this concentration gradient